For corrosion resistance the PRO Stainless sets a new benchmark. Internal reinforcements, precision-tooled pulley blocks with inline wheels to prevent line twisting (suitable only for sails with correct pulley orientation) and superb transfer of power. Marine-grade stainless steel not only prevents corrosion but offers the most comprehensive protection against wear of moving parts. Invest in one of these and even your great-great-grandchildren will thank you. Available sizes: 15cm.